OpenGLRenderer.cpp revision 8d0d4783a0206c5884bf0b958d181f450ba5207d 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "OpenGLRenderer"
18
19#include <stdlib.h>
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <SkCanvas.h>
24#include <SkTypeface.h>
25
26#include <utils/Log.h>
27#include <utils/StopWatch.h>
28
29#include <ui/Rect.h>
30
31#include "OpenGLRenderer.h"
32#include "DisplayListRenderer.h"
33#include "Vector.h"
34
35namespace android {
36namespace uirenderer {
37
38///////////////////////////////////////////////////////////////////////////////
39// Defines
40///////////////////////////////////////////////////////////////////////////////
41
42#define RAD_TO_DEG (180.0f / 3.14159265f)
43#define MIN_ANGLE 0.001f
44
45// TODO: This should be set in properties
46#define ALPHA_THRESHOLD (0x7f / PANEL_BIT_DEPTH)
47
48///////////////////////////////////////////////////////////////////////////////
49// Globals
50///////////////////////////////////////////////////////////////////////////////
51
52/**
53 * Structure mapping Skia xfermodes to OpenGL blending factors.
54 */
55struct Blender {
56    SkXfermode::Mode mode;
57    GLenum src;
58    GLenum dst;
59}; // struct Blender
60
61// In this array, the index of each Blender equals the value of the first
62// entry. For instance, gBlends[1] == gBlends[SkXfermode::kSrc_Mode]
63static const Blender gBlends[] = {
64        { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
65        { SkXfermode::kSrc_Mode,     GL_ONE,                  GL_ZERO },
66        { SkXfermode::kDst_Mode,     GL_ZERO,                 GL_ONE },
67        { SkXfermode::kSrcOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
68        { SkXfermode::kDstOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
69        { SkXfermode::kSrcIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
70        { SkXfermode::kDstIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
71        { SkXfermode::kSrcOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
72        { SkXfermode::kDstOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
73        { SkXfermode::kSrcATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
74        { SkXfermode::kDstATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
75        { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
76};
77
78// This array contains the swapped version of each SkXfermode. For instance
79// this array's SrcOver blending mode is actually DstOver. You can refer to
80// createLayer() for more information on the purpose of this array.
81static const Blender gBlendsSwap[] = {
82        { SkXfermode::kClear_Mode,   GL_ZERO,                 GL_ZERO },
83        { SkXfermode::kSrc_Mode,     GL_ZERO,                 GL_ONE },
84        { SkXfermode::kDst_Mode,     GL_ONE,                  GL_ZERO },
85        { SkXfermode::kSrcOver_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_ONE },
86        { SkXfermode::kDstOver_Mode, GL_ONE,                  GL_ONE_MINUS_SRC_ALPHA },
87        { SkXfermode::kSrcIn_Mode,   GL_ZERO,                 GL_SRC_ALPHA },
88        { SkXfermode::kDstIn_Mode,   GL_DST_ALPHA,            GL_ZERO },
89        { SkXfermode::kSrcOut_Mode,  GL_ZERO,                 GL_ONE_MINUS_SRC_ALPHA },
90        { SkXfermode::kDstOut_Mode,  GL_ONE_MINUS_DST_ALPHA,  GL_ZERO },
91        { SkXfermode::kSrcATop_Mode, GL_ONE_MINUS_DST_ALPHA,  GL_SRC_ALPHA },
92        { SkXfermode::kDstATop_Mode, GL_DST_ALPHA,            GL_ONE_MINUS_SRC_ALPHA },
93        { SkXfermode::kXor_Mode,     GL_ONE_MINUS_DST_ALPHA,  GL_ONE_MINUS_SRC_ALPHA }
94};
95
96static const GLenum gTextureUnits[] = {
97        GL_TEXTURE0,
98        GL_TEXTURE1,
99        GL_TEXTURE2
100};
101
102///////////////////////////////////////////////////////////////////////////////
103// Constructors/destructor
104///////////////////////////////////////////////////////////////////////////////
105
106OpenGLRenderer::OpenGLRenderer(): mCaches(Caches::getInstance()) {
107    mShader = NULL;
108    mColorFilter = NULL;
109    mHasShadow = false;
110
111    memcpy(mMeshVertices, gMeshVertices, sizeof(gMeshVertices));
112
113    mFirstSnapshot = new Snapshot;
114}
115
116OpenGLRenderer::~OpenGLRenderer() {
117    // The context has already been destroyed at this point, do not call
118    // GL APIs. All GL state should be kept in Caches.h
119}
120
121///////////////////////////////////////////////////////////////////////////////
122// Setup
123///////////////////////////////////////////////////////////////////////////////
124
125void OpenGLRenderer::setViewport(int width, int height) {
126    glViewport(0, 0, width, height);
127    mOrthoMatrix.loadOrtho(0, width, height, 0, -1, 1);
128
129    mWidth = width;
130    mHeight = height;
131
132    mFirstSnapshot->height = height;
133    mFirstSnapshot->viewport.set(0, 0, width, height);
134
135    mDirtyClip = false;
136}
137
138void OpenGLRenderer::prepare(bool opaque) {
139    mCaches.clearGarbage();
140
141    mSnapshot = new Snapshot(mFirstSnapshot,
142            SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
143    mSaveCount = 1;
144
145    glViewport(0, 0, mWidth, mHeight);
146
147    glDisable(GL_DITHER);
148
149    if (!opaque) {
150        glDisable(GL_SCISSOR_TEST);
151        glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
152        glClear(GL_COLOR_BUFFER_BIT);
153    }
154
155    glEnable(GL_SCISSOR_TEST);
156    glScissor(0, 0, mWidth, mHeight);
157    mSnapshot->setClip(0.0f, 0.0f, mWidth, mHeight);
158}
159
160void OpenGLRenderer::finish() {
161#if DEBUG_OPENGL
162    GLenum status = GL_NO_ERROR;
163    while ((status = glGetError()) != GL_NO_ERROR) {
164        LOGD("GL error from OpenGLRenderer: 0x%x", status);
165    }
166#endif
167#if DEBUG_MEMORY_USAGE
168    mCaches.dumpMemoryUsage();
169#else
170    if (mCaches.getDebugLevel() & kDebugMemory) {
171        mCaches.dumpMemoryUsage();
172    }
173#endif
174}
175
176void OpenGLRenderer::acquireContext() {
177    if (mCaches.currentProgram) {
178        if (mCaches.currentProgram->isInUse()) {
179            mCaches.currentProgram->remove();
180            mCaches.currentProgram = NULL;
181        }
182    }
183    mCaches.unbindMeshBuffer();
184}
185
186void OpenGLRenderer::releaseContext() {
187    glViewport(0, 0, mSnapshot->viewport.getWidth(), mSnapshot->viewport.getHeight());
188
189    glEnable(GL_SCISSOR_TEST);
190    dirtyClip();
191
192    glDisable(GL_DITHER);
193
194    glBindFramebuffer(GL_FRAMEBUFFER, 0);
195    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
196
197    mCaches.blend = true;
198    glEnable(GL_BLEND);
199    glBlendFunc(mCaches.lastSrcMode, mCaches.lastDstMode);
200    glBlendEquation(GL_FUNC_ADD);
201}
202
203///////////////////////////////////////////////////////////////////////////////
204// State management
205///////////////////////////////////////////////////////////////////////////////
206
207int OpenGLRenderer::getSaveCount() const {
208    return mSaveCount;
209}
210
211int OpenGLRenderer::save(int flags) {
212    return saveSnapshot(flags);
213}
214
215void OpenGLRenderer::restore() {
216    if (mSaveCount > 1) {
217        restoreSnapshot();
218    }
219}
220
221void OpenGLRenderer::restoreToCount(int saveCount) {
222    if (saveCount < 1) saveCount = 1;
223
224    while (mSaveCount > saveCount) {
225        restoreSnapshot();
226    }
227}
228
229int OpenGLRenderer::saveSnapshot(int flags) {
230    mSnapshot = new Snapshot(mSnapshot, flags);
231    return mSaveCount++;
232}
233
234bool OpenGLRenderer::restoreSnapshot() {
235    bool restoreClip = mSnapshot->flags & Snapshot::kFlagClipSet;
236    bool restoreLayer = mSnapshot->flags & Snapshot::kFlagIsLayer;
237    bool restoreOrtho = mSnapshot->flags & Snapshot::kFlagDirtyOrtho;
238
239    sp<Snapshot> current = mSnapshot;
240    sp<Snapshot> previous = mSnapshot->previous;
241
242    if (restoreOrtho) {
243        Rect& r = previous->viewport;
244        glViewport(r.left, r.top, r.right, r.bottom);
245        mOrthoMatrix.load(current->orthoMatrix);
246    }
247
248    mSaveCount--;
249    mSnapshot = previous;
250
251    if (restoreClip) {
252        dirtyClip();
253    }
254
255    if (restoreLayer) {
256        composeLayer(current, previous);
257    }
258
259    return restoreClip;
260}
261
262///////////////////////////////////////////////////////////////////////////////
263// Layers
264///////////////////////////////////////////////////////////////////////////////
265
266int OpenGLRenderer::saveLayer(float left, float top, float right, float bottom,
267        SkPaint* p, int flags) {
268    const GLuint previousFbo = mSnapshot->fbo;
269    const int count = saveSnapshot(flags);
270
271    if (!mSnapshot->isIgnored()) {
272        int alpha = 255;
273        SkXfermode::Mode mode;
274
275        if (p) {
276            alpha = p->getAlpha();
277            if (!mCaches.extensions.hasFramebufferFetch()) {
278                const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
279                if (!isMode) {
280                    // Assume SRC_OVER
281                    mode = SkXfermode::kSrcOver_Mode;
282                }
283            } else {
284                mode = getXfermode(p->getXfermode());
285            }
286        } else {
287            mode = SkXfermode::kSrcOver_Mode;
288        }
289
290        createLayer(mSnapshot, left, top, right, bottom, alpha, mode, flags, previousFbo);
291    }
292
293    return count;
294}
295
296int OpenGLRenderer::saveLayerAlpha(float left, float top, float right, float bottom,
297        int alpha, int flags) {
298    if (alpha >= 255 - ALPHA_THRESHOLD) {
299        return saveLayer(left, top, right, bottom, NULL, flags);
300    } else {
301        SkPaint paint;
302        paint.setAlpha(alpha);
303        return saveLayer(left, top, right, bottom, &paint, flags);
304    }
305}
306
307/**
308 * Layers are viewed by Skia are slightly different than layers in image editing
309 * programs (for instance.) When a layer is created, previously created layers
310 * and the frame buffer still receive every drawing command. For instance, if a
311 * layer is created and a shape intersecting the bounds of the layers and the
312 * framebuffer is draw, the shape will be drawn on both (unless the layer was
313 * created with the SkCanvas::kClipToLayer_SaveFlag flag.)
314 *
315 * A way to implement layers is to create an FBO for each layer, backed by an RGBA
316 * texture. Unfortunately, this is inefficient as it requires every primitive to
317 * be drawn n + 1 times, where n is the number of active layers. In practice this
318 * means, for every primitive:
319 *   - Switch active frame buffer
320 *   - Change viewport, clip and projection matrix
321 *   - Issue the drawing
322 *
323 * Switching rendering target n + 1 times per drawn primitive is extremely costly.
324 * To avoid this, layers are implemented in a different way here, at least in the
325 * general case. FBOs are used, as an optimization, when the "clip to layer" flag
326 * is set. When this flag is set we can redirect all drawing operations into a
327 * single FBO.
328 *
329 * This implementation relies on the frame buffer being at least RGBA 8888. When
330 * a layer is created, only a texture is created, not an FBO. The content of the
331 * frame buffer contained within the layer's bounds is copied into this texture
332 * using glCopyTexImage2D(). The layer's region is then cleared(1) in the frame
333 * buffer and drawing continues as normal. This technique therefore treats the
334 * frame buffer as a scratch buffer for the layers.
335 *
336 * To compose the layers back onto the frame buffer, each layer texture
337 * (containing the original frame buffer data) is drawn as a simple quad over
338 * the frame buffer. The trick is that the quad is set as the composition
339 * destination in the blending equation, and the frame buffer becomes the source
340 * of the composition.
341 *
342 * Drawing layers with an alpha value requires an extra step before composition.
343 * An empty quad is drawn over the layer's region in the frame buffer. This quad
344 * is drawn with the rgba color (0,0,0,alpha). The alpha value offered by the
345 * quad is used to multiply the colors in the frame buffer. This is achieved by
346 * changing the GL blend functions for the GL_FUNC_ADD blend equation to
347 * GL_ZERO, GL_SRC_ALPHA.
348 *
349 * Because glCopyTexImage2D() can be slow, an alternative implementation might
350 * be use to draw a single clipped layer. The implementation described above
351 * is correct in every case.
352 *
353 * (1) The frame buffer is actually not cleared right away. To allow the GPU
354 *     to potentially optimize series of calls to glCopyTexImage2D, the frame
355 *     buffer is left untouched until the first drawing operation. Only when
356 *     something actually gets drawn are the layers regions cleared.
357 */
358bool OpenGLRenderer::createLayer(sp<Snapshot> snapshot, float left, float top,
359        float right, float bottom, int alpha, SkXfermode::Mode mode,
360        int flags, GLuint previousFbo) {
361    LAYER_LOGD("Requesting layer %.2fx%.2f", right - left, bottom - top);
362    LAYER_LOGD("Layer cache size = %d", mCaches.layerCache.getSize());
363
364    const bool fboLayer = flags & SkCanvas::kClipToLayer_SaveFlag;
365
366    // Window coordinates of the layer
367    Rect bounds(left, top, right, bottom);
368    if (fboLayer) {
369        // Clear the previous layer regions before we change the viewport
370        clearLayerRegions();
371    } else {
372        mSnapshot->transform->mapRect(bounds);
373
374        // Layers only make sense if they are in the framebuffer's bounds
375        bounds.intersect(*snapshot->clipRect);
376
377        // We cannot work with sub-pixels in this case
378        bounds.snapToPixelBoundaries();
379
380        // When the layer is not an FBO, we may use glCopyTexImage so we
381        // need to make sure the layer does not extend outside the bounds
382        // of the framebuffer
383        bounds.intersect(snapshot->previous->viewport);
384    }
385
386    if (bounds.isEmpty() || bounds.getWidth() > mCaches.maxTextureSize ||
387            bounds.getHeight() > mCaches.maxTextureSize) {
388        snapshot->empty = fboLayer;
389    } else {
390        snapshot->invisible = snapshot->invisible || (alpha <= ALPHA_THRESHOLD && fboLayer);
391    }
392
393    // Bail out if we won't draw in this snapshot
394    if (snapshot->invisible || snapshot->empty) {
395        return false;
396    }
397
398    glActiveTexture(gTextureUnits[0]);
399    Layer* layer = mCaches.layerCache.get(bounds.getWidth(), bounds.getHeight());
400    if (!layer) {
401        return false;
402    }
403
404    layer->mode = mode;
405    layer->alpha = alpha;
406    layer->layer.set(bounds);
407    layer->texCoords.set(0.0f, bounds.getHeight() / float(layer->height),
408            bounds.getWidth() / float(layer->width), 0.0f);
409
410    // Save the layer in the snapshot
411    snapshot->flags |= Snapshot::kFlagIsLayer;
412    snapshot->layer = layer;
413
414    if (fboLayer) {
415        return createFboLayer(layer, bounds, snapshot, previousFbo);
416    } else {
417        // Copy the framebuffer into the layer
418        glBindTexture(GL_TEXTURE_2D, layer->texture);
419
420        if (layer->empty) {
421            glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bounds.left,
422                    snapshot->height - bounds.bottom, layer->width, layer->height, 0);
423            layer->empty = false;
424        } else {
425            glCopyTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bounds.left,
426                    snapshot->height - bounds.bottom, bounds.getWidth(), bounds.getHeight());
427        }
428
429        // Enqueue the buffer coordinates to clear the corresponding region later
430        mLayers.push(new Rect(bounds));
431    }
432
433    return true;
434}
435
436bool OpenGLRenderer::createFboLayer(Layer* layer, Rect& bounds, sp<Snapshot> snapshot,
437        GLuint previousFbo) {
438    layer->fbo = mCaches.fboCache.get();
439
440#if RENDER_LAYERS_AS_REGIONS
441    snapshot->region = &snapshot->layer->region;
442    snapshot->flags |= Snapshot::kFlagFboTarget;
443#endif
444
445    Rect clip(bounds);
446    snapshot->transform->mapRect(clip);
447    clip.intersect(*snapshot->clipRect);
448    clip.snapToPixelBoundaries();
449    clip.intersect(snapshot->previous->viewport);
450
451    mat4 inverse;
452    inverse.loadInverse(*mSnapshot->transform);
453
454    inverse.mapRect(clip);
455    clip.snapToPixelBoundaries();
456    clip.intersect(bounds);
457    clip.translate(-bounds.left, -bounds.top);
458
459    snapshot->flags |= Snapshot::kFlagIsFboLayer;
460    snapshot->fbo = layer->fbo;
461    snapshot->resetTransform(-bounds.left, -bounds.top, 0.0f);
462    //snapshot->resetClip(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
463    snapshot->resetClip(clip.left, clip.top, clip.right, clip.bottom);
464    snapshot->viewport.set(0.0f, 0.0f, bounds.getWidth(), bounds.getHeight());
465    snapshot->height = bounds.getHeight();
466    snapshot->flags |= Snapshot::kFlagDirtyOrtho;
467    snapshot->orthoMatrix.load(mOrthoMatrix);
468
469    // Bind texture to FBO
470    glBindFramebuffer(GL_FRAMEBUFFER, layer->fbo);
471    glBindTexture(GL_TEXTURE_2D, layer->texture);
472
473    // Initialize the texture if needed
474    if (layer->empty) {
475        layer->empty = false;
476        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, layer->width, layer->height, 0,
477                GL_RGBA, GL_UNSIGNED_BYTE, NULL);
478    }
479
480    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
481            layer->texture, 0);
482
483#if DEBUG_LAYERS_AS_REGIONS
484    GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
485    if (status != GL_FRAMEBUFFER_COMPLETE) {
486        LOGE("Framebuffer incomplete (GL error code 0x%x)", status);
487
488        glBindFramebuffer(GL_FRAMEBUFFER, previousFbo);
489        glDeleteTextures(1, &layer->texture);
490        mCaches.fboCache.put(layer->fbo);
491
492        delete layer;
493
494        return false;
495    }
496#endif
497
498    // Clear the FBO, expand the clear region by 1 to get nice bilinear filtering
499    glScissor(clip.left - 1.0f, bounds.getHeight() - clip.bottom - 1.0f,
500            clip.getWidth() + 2.0f, clip.getHeight() + 2.0f);
501    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
502    glClear(GL_COLOR_BUFFER_BIT);
503
504    dirtyClip();
505
506    // Change the ortho projection
507    glViewport(0, 0, bounds.getWidth(), bounds.getHeight());
508    mOrthoMatrix.loadOrtho(0.0f, bounds.getWidth(), bounds.getHeight(), 0.0f, -1.0f, 1.0f);
509
510    return true;
511}
512
513/**
514 * Read the documentation of createLayer() before doing anything in this method.
515 */
516void OpenGLRenderer::composeLayer(sp<Snapshot> current, sp<Snapshot> previous) {
517    if (!current->layer) {
518        LOGE("Attempting to compose a layer that does not exist");
519        return;
520    }
521
522    const bool fboLayer = current->flags & Snapshot::kFlagIsFboLayer;
523
524    if (fboLayer) {
525        // Unbind current FBO and restore previous one
526        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
527    }
528
529    Layer* layer = current->layer;
530    const Rect& rect = layer->layer;
531
532    if (!fboLayer && layer->alpha < 255) {
533        drawColorRect(rect.left, rect.top, rect.right, rect.bottom,
534                layer->alpha << 24, SkXfermode::kDstIn_Mode, true);
535        // Required below, composeLayerRect() will divide by 255
536        layer->alpha = 255;
537    }
538
539    mCaches.unbindMeshBuffer();
540
541    glActiveTexture(gTextureUnits[0]);
542
543    // When the layer is stored in an FBO, we can save a bit of fillrate by
544    // drawing only the dirty region
545    if (fboLayer) {
546        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom, *previous->transform);
547        composeLayerRegion(layer, rect);
548    } else {
549        dirtyLayer(rect.left, rect.top, rect.right, rect.bottom);
550        composeLayerRect(layer, rect, true);
551    }
552
553    if (fboLayer) {
554        // Detach the texture from the FBO
555        glBindFramebuffer(GL_FRAMEBUFFER, current->fbo);
556        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, 0, 0);
557        glBindFramebuffer(GL_FRAMEBUFFER, previous->fbo);
558
559        // Put the FBO name back in the cache, if it doesn't fit, it will be destroyed
560        mCaches.fboCache.put(current->fbo);
561    }
562
563    dirtyClip();
564
565    // Failing to add the layer to the cache should happen only if the layer is too large
566    if (!mCaches.layerCache.put(layer)) {
567        LAYER_LOGD("Deleting layer");
568        glDeleteTextures(1, &layer->texture);
569        delete layer;
570    }
571}
572
573void OpenGLRenderer::composeLayerRect(Layer* layer, const Rect& rect, bool swap) {
574    const Rect& texCoords = layer->texCoords;
575    resetDrawTextureTexCoords(texCoords.left, texCoords.top, texCoords.right, texCoords.bottom);
576
577    drawTextureMesh(rect.left, rect.top, rect.right, rect.bottom, layer->texture,
578            layer->alpha / 255.0f, layer->mode, layer->blend, &mMeshVertices[0].position[0],
579            &mMeshVertices[0].texture[0], GL_TRIANGLE_STRIP, gMeshCount, swap, swap);
580
581    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
582}
583
584void OpenGLRenderer::composeLayerRegion(Layer* layer, const Rect& rect) {
585#if RENDER_LAYERS_AS_REGIONS
586    if (layer->region.isRect()) {
587        composeLayerRect(layer, rect);
588        layer->region.clear();
589        return;
590    }
591
592    if (!layer->region.isEmpty()) {
593        size_t count;
594        const android::Rect* rects = layer->region.getArray(&count);
595
596        setupDraw();
597
598        ProgramDescription description;
599        description.hasTexture = true;
600
601        const float alpha = layer->alpha / 255.0f;
602        const bool setColor = description.setColor(alpha, alpha, alpha, alpha);
603        chooseBlending(layer->blend || layer->alpha < 255, layer->mode, description, false);
604
605        useProgram(mCaches.programCache.get(description));
606
607        // Texture
608        bindTexture(layer->texture);
609        glUniform1i(mCaches.currentProgram->getUniform("sampler"), 0);
610
611        // Always premultiplied
612        if (setColor) {
613            mCaches.currentProgram->setColor(alpha, alpha, alpha, alpha);
614        }
615
616        // Mesh
617        int texCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
618        glEnableVertexAttribArray(texCoordsSlot);
619
620        mModelView.loadIdentity();
621        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
622
623        const float texX = 1.0f / float(layer->width);
624        const float texY = 1.0f / float(layer->height);
625
626        TextureVertex* mesh = mCaches.getRegionMesh();
627        GLsizei numQuads = 0;
628
629        glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
630                gMeshStride, &mesh[0].position[0]);
631        glVertexAttribPointer(texCoordsSlot, 2, GL_FLOAT, GL_FALSE,
632                gMeshStride, &mesh[0].texture[0]);
633
634        for (size_t i = 0; i < count; i++) {
635            const android::Rect* r = &rects[i];
636
637            const float u1 = r->left * texX;
638            const float v1 = (rect.getHeight() - r->top) * texY;
639            const float u2 = r->right * texX;
640            const float v2 = (rect.getHeight() - r->bottom) * texY;
641
642            // TODO: Reject quads outside of the clip
643            TextureVertex::set(mesh++, r->left, r->top, u1, v1);
644            TextureVertex::set(mesh++, r->right, r->top, u2, v1);
645            TextureVertex::set(mesh++, r->left, r->bottom, u1, v2);
646            TextureVertex::set(mesh++, r->right, r->bottom, u2, v2);
647
648            numQuads++;
649
650            if (numQuads >= REGION_MESH_QUAD_COUNT) {
651                glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
652                numQuads = 0;
653                mesh = mCaches.getRegionMesh();
654            }
655        }
656
657        if (numQuads > 0) {
658            glDrawElements(GL_TRIANGLES, numQuads * 6, GL_UNSIGNED_SHORT, NULL);
659        }
660
661        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
662        glDisableVertexAttribArray(texCoordsSlot);
663
664#if DEBUG_LAYERS_AS_REGIONS
665        uint32_t colors[] = {
666                0x7fff0000, 0x7f00ff00,
667                0x7f0000ff, 0x7fff00ff,
668        };
669
670        int offset = 0;
671        int32_t top = rects[0].top;
672        int i = 0;
673
674        for (size_t i = 0; i < count; i++) {
675            if (top != rects[i].top) {
676                offset ^= 0x2;
677                top = rects[i].top;
678            }
679
680            Rect r(rects[i].left, rects[i].top, rects[i].right, rects[i].bottom);
681            drawColorRect(r.left, r.top, r.right, r.bottom, colors[offset + (i & 0x1)],
682                    SkXfermode::kSrcOver_Mode);
683        }
684#endif
685
686        layer->region.clear();
687    }
688#else
689    composeLayerRect(layer, rect);
690#endif
691}
692
693void OpenGLRenderer::dirtyLayer(const float left, const float top,
694        const float right, const float bottom, const mat4 transform) {
695#if RENDER_LAYERS_AS_REGIONS
696    if ((mSnapshot->flags & Snapshot::kFlagFboTarget) && mSnapshot->region) {
697        Rect bounds(left, top, right, bottom);
698        transform.mapRect(bounds);
699        bounds.intersect(*mSnapshot->clipRect);
700        bounds.snapToPixelBoundaries();
701
702        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
703        if (!dirty.isEmpty()) {
704            mSnapshot->region->orSelf(dirty);
705        }
706    }
707#endif
708}
709
710void OpenGLRenderer::dirtyLayer(const float left, const float top,
711        const float right, const float bottom) {
712#if RENDER_LAYERS_AS_REGIONS
713    if ((mSnapshot->flags & Snapshot::kFlagFboTarget) && mSnapshot->region) {
714        Rect bounds(left, top, right, bottom);
715        bounds.intersect(*mSnapshot->clipRect);
716        bounds.snapToPixelBoundaries();
717
718        android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
719        if (!dirty.isEmpty()) {
720            mSnapshot->region->orSelf(dirty);
721        }
722    }
723#endif
724}
725
726void OpenGLRenderer::clearLayerRegions() {
727    if (mLayers.size() == 0 || mSnapshot->isIgnored()) return;
728
729    Rect clipRect(*mSnapshot->clipRect);
730    clipRect.snapToPixelBoundaries();
731
732    for (uint32_t i = 0; i < mLayers.size(); i++) {
733        Rect* bounds = mLayers.itemAt(i);
734        if (clipRect.intersects(*bounds)) {
735            // Clear the framebuffer where the layer will draw
736            glScissor(bounds->left, mSnapshot->height - bounds->bottom,
737                    bounds->getWidth(), bounds->getHeight());
738            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
739            glClear(GL_COLOR_BUFFER_BIT);
740
741            // Restore the clip
742            dirtyClip();
743        }
744
745        delete bounds;
746    }
747
748    mLayers.clear();
749}
750
751///////////////////////////////////////////////////////////////////////////////
752// Transforms
753///////////////////////////////////////////////////////////////////////////////
754
755void OpenGLRenderer::translate(float dx, float dy) {
756    mSnapshot->transform->translate(dx, dy, 0.0f);
757}
758
759void OpenGLRenderer::rotate(float degrees) {
760    mSnapshot->transform->rotate(degrees, 0.0f, 0.0f, 1.0f);
761}
762
763void OpenGLRenderer::scale(float sx, float sy) {
764    mSnapshot->transform->scale(sx, sy, 1.0f);
765}
766
767void OpenGLRenderer::setMatrix(SkMatrix* matrix) {
768    mSnapshot->transform->load(*matrix);
769}
770
771const float* OpenGLRenderer::getMatrix() const {
772    if (mSnapshot->fbo != 0) {
773        return &mSnapshot->transform->data[0];
774    }
775    return &mIdentity.data[0];
776}
777
778void OpenGLRenderer::getMatrix(SkMatrix* matrix) {
779    mSnapshot->transform->copyTo(*matrix);
780}
781
782void OpenGLRenderer::concatMatrix(SkMatrix* matrix) {
783    SkMatrix transform;
784    mSnapshot->transform->copyTo(transform);
785    transform.preConcat(*matrix);
786    mSnapshot->transform->load(transform);
787}
788
789///////////////////////////////////////////////////////////////////////////////
790// Clipping
791///////////////////////////////////////////////////////////////////////////////
792
793void OpenGLRenderer::setScissorFromClip() {
794    Rect clip(*mSnapshot->clipRect);
795    clip.snapToPixelBoundaries();
796    glScissor(clip.left, mSnapshot->height - clip.bottom, clip.getWidth(), clip.getHeight());
797    mDirtyClip = false;
798}
799
800const Rect& OpenGLRenderer::getClipBounds() {
801    return mSnapshot->getLocalClip();
802}
803
804bool OpenGLRenderer::quickReject(float left, float top, float right, float bottom) {
805    if (mSnapshot->isIgnored()) {
806        return true;
807    }
808
809    Rect r(left, top, right, bottom);
810    mSnapshot->transform->mapRect(r);
811    r.snapToPixelBoundaries();
812
813    Rect clipRect(*mSnapshot->clipRect);
814    clipRect.snapToPixelBoundaries();
815
816    return !clipRect.intersects(r);
817}
818
819bool OpenGLRenderer::clipRect(float left, float top, float right, float bottom, SkRegion::Op op) {
820    bool clipped = mSnapshot->clip(left, top, right, bottom, op);
821    if (clipped) {
822        dirtyClip();
823    }
824    return !mSnapshot->clipRect->isEmpty();
825}
826
827///////////////////////////////////////////////////////////////////////////////
828// Drawing commands
829///////////////////////////////////////////////////////////////////////////////
830
831void OpenGLRenderer::setupDraw() {
832    clearLayerRegions();
833    if (mDirtyClip) {
834        setScissorFromClip();
835    }
836    mDescription.reset();
837    mSetShaderColor = false;
838    mColorSet = false;
839    mColorA = mColorR = mColorG = mColorB = 0.0f;
840    mTextureUnit = 0;
841    mTrackDirtyRegions = true;
842    mTexCoordsSlot = -1;
843}
844
845void OpenGLRenderer::setupDrawWithTexture(bool isAlpha8) {
846    mDescription.hasTexture = true;
847    mDescription.hasAlpha8Texture = isAlpha8;
848}
849
850void OpenGLRenderer::setupDrawColor(int color) {
851    setupDrawColor(color, (color >> 24) & 0xFF);
852}
853
854void OpenGLRenderer::setupDrawColor(int color, int alpha) {
855    mColorA = alpha / 255.0f;
856    const float a = mColorA / 255.0f;
857    mColorR = a * ((color >> 16) & 0xFF);
858    mColorG = a * ((color >>  8) & 0xFF);
859    mColorB = a * ((color      ) & 0xFF);
860    mColorSet = true;
861    mSetShaderColor = mDescription.setColor(mColorR, mColorG, mColorB, mColorA);
862}
863
864void OpenGLRenderer::setupDrawAlpha8Color(int color, int alpha) {
865    mColorA = alpha / 255.0f;
866    const float a = mColorA / 255.0f;
867    mColorR = a * ((color >> 16) & 0xFF);
868    mColorG = a * ((color >>  8) & 0xFF);
869    mColorB = a * ((color      ) & 0xFF);
870    mColorSet = true;
871    mSetShaderColor = mDescription.setAlpha8Color(mColorR, mColorG, mColorB, mColorA);
872}
873
874void OpenGLRenderer::setupDrawColor(float r, float g, float b, float a) {
875    mColorA = a;
876    mColorR = r;
877    mColorG = g;
878    mColorB = b;
879    mColorSet = true;
880    mSetShaderColor = mDescription.setColor(r, g, b, a);
881}
882
883void OpenGLRenderer::setupDrawAlpha8Color(float r, float g, float b, float a) {
884    mColorA = a;
885    mColorR = r;
886    mColorG = g;
887    mColorB = b;
888    mColorSet = true;
889    mSetShaderColor = mDescription.setAlpha8Color(r, g, b, a);
890}
891
892void OpenGLRenderer::setupDrawShader() {
893    if (mShader) {
894        mShader->describe(mDescription, mCaches.extensions);
895    }
896}
897
898void OpenGLRenderer::setupDrawColorFilter() {
899    if (mColorFilter) {
900        mColorFilter->describe(mDescription, mCaches.extensions);
901    }
902}
903
904void OpenGLRenderer::setupDrawBlending(SkXfermode::Mode mode, bool swapSrcDst) {
905    chooseBlending((mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
906            mDescription, swapSrcDst);
907}
908
909void OpenGLRenderer::setupDrawBlending(bool blend, SkXfermode::Mode mode, bool swapSrcDst) {
910    chooseBlending(blend || (mColorSet && mColorA < 1.0f) || (mShader && mShader->blend()), mode,
911            mDescription, swapSrcDst);
912}
913
914void OpenGLRenderer::setupDrawProgram() {
915    useProgram(mCaches.programCache.get(mDescription));
916}
917
918void OpenGLRenderer::setupDrawDirtyRegionsDisabled() {
919    mTrackDirtyRegions = false;
920}
921
922void OpenGLRenderer::setupDrawModelViewTranslate(float left, float top, float right, float bottom,
923        bool ignoreTransform) {
924    mModelView.loadTranslate(left, top, 0.0f);
925    if (!ignoreTransform) {
926        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
927        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
928    } else {
929        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
930        if (mTrackDirtyRegions) dirtyLayer(left, top, right, bottom);
931    }
932}
933
934void OpenGLRenderer::setupDrawModelViewIdentity() {
935    mCaches.currentProgram->set(mOrthoMatrix, mIdentity, *mSnapshot->transform);
936}
937
938void OpenGLRenderer::setupDrawModelView(float left, float top, float right, float bottom,
939        bool ignoreTransform, bool ignoreModelView) {
940    if (!ignoreModelView) {
941        mModelView.loadTranslate(left, top, 0.0f);
942        mModelView.scale(right - left, bottom - top, 1.0f);
943    } else {
944        mModelView.loadIdentity();
945    }
946    bool dirty = right - left > 0.0f && bottom - top > 0.0f;
947    if (!ignoreTransform) {
948        mCaches.currentProgram->set(mOrthoMatrix, mModelView, *mSnapshot->transform);
949        if (mTrackDirtyRegions && dirty) {
950            dirtyLayer(left, top, right, bottom, *mSnapshot->transform);
951        }
952    } else {
953        mCaches.currentProgram->set(mOrthoMatrix, mModelView, mIdentity);
954        if (mTrackDirtyRegions && dirty) dirtyLayer(left, top, right, bottom);
955    }
956}
957
958void OpenGLRenderer::setupDrawColorUniforms() {
959    if (mColorSet || (mShader && mSetShaderColor)) {
960        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
961    }
962}
963
964void OpenGLRenderer::setupDrawPureColorUniforms() {
965    if (mSetShaderColor) {
966        mCaches.currentProgram->setColor(mColorR, mColorG, mColorB, mColorA);
967    }
968}
969
970void OpenGLRenderer::setupDrawShaderUniforms(bool ignoreTransform) {
971    if (mShader) {
972        if (ignoreTransform) {
973            mModelView.loadInverse(*mSnapshot->transform);
974        }
975        mShader->setupProgram(mCaches.currentProgram, mModelView, *mSnapshot, &mTextureUnit);
976    }
977}
978
979void OpenGLRenderer::setupDrawShaderIdentityUniforms() {
980    if (mShader) {
981        mShader->setupProgram(mCaches.currentProgram, mIdentity, *mSnapshot, &mTextureUnit);
982    }
983}
984
985void OpenGLRenderer::setupDrawColorFilterUniforms() {
986    if (mColorFilter) {
987        mColorFilter->setupProgram(mCaches.currentProgram);
988    }
989}
990
991void OpenGLRenderer::setupDrawSimpleMesh() {
992    mCaches.bindMeshBuffer();
993    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
994            gMeshStride, 0);
995}
996
997void OpenGLRenderer::setupDrawTexture(GLuint texture) {
998    bindTexture(texture);
999    glUniform1i(mCaches.currentProgram->getUniform("sampler"), mTextureUnit++);
1000
1001    mTexCoordsSlot = mCaches.currentProgram->getAttrib("texCoords");
1002    glEnableVertexAttribArray(mTexCoordsSlot);
1003}
1004
1005void OpenGLRenderer::setupDrawMesh(GLvoid* vertices, GLvoid* texCoords, GLuint vbo) {
1006    if (!vertices) {
1007        mCaches.bindMeshBuffer(vbo == 0 ? mCaches.meshBuffer : vbo);
1008    } else {
1009        mCaches.unbindMeshBuffer();
1010    }
1011    glVertexAttribPointer(mCaches.currentProgram->position, 2, GL_FLOAT, GL_FALSE,
1012            gMeshStride, vertices);
1013    if (mTexCoordsSlot > 0) {
1014        glVertexAttribPointer(mTexCoordsSlot, 2, GL_FLOAT, GL_FALSE, gMeshStride, texCoords);
1015    }
1016}
1017
1018void OpenGLRenderer::finishDrawTexture() {
1019    glDisableVertexAttribArray(mTexCoordsSlot);
1020}
1021
1022///////////////////////////////////////////////////////////////////////////////
1023// Drawing
1024///////////////////////////////////////////////////////////////////////////////
1025
1026void OpenGLRenderer::drawDisplayList(DisplayList* displayList) {
1027    // All the usual checks and setup operations (quickReject, setupDraw, etc.)
1028    // will be performed by the display list itself
1029    if (displayList) {
1030        displayList->replay(*this);
1031    }
1032}
1033
1034void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, float left, float top, SkPaint* paint) {
1035    const float right = left + bitmap->width();
1036    const float bottom = top + bitmap->height();
1037
1038    if (quickReject(left, top, right, bottom)) {
1039        return;
1040    }
1041
1042    glActiveTexture(gTextureUnits[0]);
1043    Texture* texture = mCaches.textureCache.get(bitmap);
1044    if (!texture) return;
1045    const AutoTexture autoCleanup(texture);
1046
1047    drawTextureRect(left, top, right, bottom, texture, paint);
1048}
1049
1050void OpenGLRenderer::drawBitmap(SkBitmap* bitmap, SkMatrix* matrix, SkPaint* paint) {
1051    Rect r(0.0f, 0.0f, bitmap->width(), bitmap->height());
1052    const mat4 transform(*matrix);
1053    transform.mapRect(r);
1054
1055    if (quickReject(r.left, r.top, r.right, r.bottom)) {
1056        return;
1057    }
1058
1059    glActiveTexture(gTextureUnits[0]);
1060    Texture* texture = mCaches.textureCache.get(bitmap);
1061    if (!texture) return;
1062    const AutoTexture autoCleanup(texture);
1063
1064    // This could be done in a cheaper way, all we need is pass the matrix
1065    // to the vertex shader. The save/restore is a bit overkill.
1066    save(SkCanvas::kMatrix_SaveFlag);
1067    concatMatrix(matrix);
1068    drawTextureRect(0.0f, 0.0f, bitmap->width(), bitmap->height(), texture, paint);
1069    restore();
1070}
1071
1072void OpenGLRenderer::drawBitmap(SkBitmap* bitmap,
1073         float srcLeft, float srcTop, float srcRight, float srcBottom,
1074         float dstLeft, float dstTop, float dstRight, float dstBottom,
1075         SkPaint* paint) {
1076    if (quickReject(dstLeft, dstTop, dstRight, dstBottom)) {
1077        return;
1078    }
1079
1080    glActiveTexture(gTextureUnits[0]);
1081    Texture* texture = mCaches.textureCache.get(bitmap);
1082    if (!texture) return;
1083    const AutoTexture autoCleanup(texture);
1084    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1085
1086    const float width = texture->width;
1087    const float height = texture->height;
1088
1089    const float u1 = srcLeft / width;
1090    const float v1 = srcTop / height;
1091    const float u2 = srcRight / width;
1092    const float v2 = srcBottom / height;
1093
1094    mCaches.unbindMeshBuffer();
1095    resetDrawTextureTexCoords(u1, v1, u2, v2);
1096
1097    int alpha;
1098    SkXfermode::Mode mode;
1099    getAlphaAndMode(paint, &alpha, &mode);
1100
1101    if (mSnapshot->transform->isPureTranslate()) {
1102        const float x = (int) floorf(dstLeft + mSnapshot->transform->getTranslateX() + 0.5f);
1103        const float y = (int) floorf(dstTop + mSnapshot->transform->getTranslateY() + 0.5f);
1104
1105        drawTextureMesh(x, y, x + (dstRight - dstLeft), y + (dstBottom - dstTop),
1106                texture->id, alpha / 255.0f, mode, texture->blend,
1107                &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1108                GL_TRIANGLE_STRIP, gMeshCount, false, true);
1109    } else {
1110        drawTextureMesh(dstLeft, dstTop, dstRight, dstBottom, texture->id, alpha / 255.0f,
1111                mode, texture->blend, &mMeshVertices[0].position[0], &mMeshVertices[0].texture[0],
1112                GL_TRIANGLE_STRIP, gMeshCount);
1113    }
1114
1115    resetDrawTextureTexCoords(0.0f, 0.0f, 1.0f, 1.0f);
1116}
1117
1118void OpenGLRenderer::drawPatch(SkBitmap* bitmap, const int32_t* xDivs, const int32_t* yDivs,
1119        const uint32_t* colors, uint32_t width, uint32_t height, int8_t numColors,
1120        float left, float top, float right, float bottom, SkPaint* paint) {
1121    if (quickReject(left, top, right, bottom)) {
1122        return;
1123    }
1124
1125    glActiveTexture(gTextureUnits[0]);
1126    Texture* texture = mCaches.textureCache.get(bitmap);
1127    if (!texture) return;
1128    const AutoTexture autoCleanup(texture);
1129    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1130
1131    int alpha;
1132    SkXfermode::Mode mode;
1133    getAlphaAndMode(paint, &alpha, &mode);
1134
1135    const Patch* mesh = mCaches.patchCache.get(bitmap->width(), bitmap->height(),
1136            right - left, bottom - top, xDivs, yDivs, colors, width, height, numColors);
1137
1138    if (mesh && mesh->verticesCount > 0) {
1139        const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1140#if RENDER_LAYERS_AS_REGIONS
1141        // Mark the current layer dirty where we are going to draw the patch
1142        if ((mSnapshot->flags & Snapshot::kFlagFboTarget) &&
1143                mSnapshot->region && mesh->hasEmptyQuads) {
1144            const size_t count = mesh->quads.size();
1145            for (size_t i = 0; i < count; i++) {
1146                const Rect& bounds = mesh->quads.itemAt(i);
1147                if (pureTranslate) {
1148                    const float x = (int) floorf(bounds.left + 0.5f);
1149                    const float y = (int) floorf(bounds.top + 0.5f);
1150                    dirtyLayer(x, y, x + bounds.getWidth(), y + bounds.getHeight(),
1151                            *mSnapshot->transform);
1152                } else {
1153                    dirtyLayer(bounds.left, bounds.top, bounds.right, bounds.bottom,
1154                            *mSnapshot->transform);
1155                }
1156            }
1157        }
1158#endif
1159
1160        if (pureTranslate) {
1161            const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1162            const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1163
1164            drawTextureMesh(x, y, x + right - left, y + bottom - top, texture->id, alpha / 255.0f,
1165                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1166                    GL_TRIANGLES, mesh->verticesCount, false, true, mesh->meshBuffer,
1167                    true, !mesh->hasEmptyQuads);
1168        } else {
1169            drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f,
1170                    mode, texture->blend, (GLvoid*) 0, (GLvoid*) gMeshTextureOffset,
1171                    GL_TRIANGLES, mesh->verticesCount, false, false, mesh->meshBuffer,
1172                    true, !mesh->hasEmptyQuads);
1173        }
1174    }
1175}
1176
1177void OpenGLRenderer::drawLines(float* points, int count, SkPaint* paint) {
1178    // TODO: Should do quickReject for each line
1179    if (mSnapshot->isIgnored()) return;
1180
1181    const bool isAA = paint->isAntiAlias();
1182    const float strokeWidth = paint->getStrokeWidth() * 0.5f;
1183    // A stroke width of 0 has a special meaningin Skia:
1184    // it draws an unscaled 1px wide line
1185    const bool isHairLine = paint->getStrokeWidth() == 0.0f;
1186
1187    int alpha;
1188    SkXfermode::Mode mode;
1189    getAlphaAndMode(paint, &alpha, &mode);
1190
1191    int verticesCount = count >> 2;
1192    if (!isHairLine) {
1193        // TODO: AA needs more vertices
1194        verticesCount *= 6;
1195    } else {
1196        // TODO: AA will be different
1197        verticesCount *= 2;
1198    }
1199
1200    TextureVertex lines[verticesCount];
1201    TextureVertex* vertex = &lines[0];
1202
1203    setupDraw();
1204    setupDrawColor(paint->getColor(), alpha);
1205    setupDrawColorFilter();
1206    setupDrawShader();
1207    setupDrawBlending(mode);
1208    setupDrawProgram();
1209    setupDrawModelViewIdentity();
1210    setupDrawColorUniforms();
1211    setupDrawColorFilterUniforms();
1212    setupDrawShaderIdentityUniforms();
1213    setupDrawMesh(vertex);
1214
1215    if (!isHairLine) {
1216        // TODO: Handle the AA case
1217        for (int i = 0; i < count; i += 4) {
1218            // a = start point, b = end point
1219            vec2 a(points[i], points[i + 1]);
1220            vec2 b(points[i + 2], points[i + 3]);
1221
1222            // Bias to snap to the same pixels as Skia
1223            a += 0.375;
1224            b += 0.375;
1225
1226            // Find the normal to the line
1227            vec2 n = (b - a).copyNormalized() * strokeWidth;
1228            float x = n.x;
1229            n.x = -n.y;
1230            n.y = x;
1231
1232            // Four corners of the rectangle defining a thick line
1233            vec2 p1 = a - n;
1234            vec2 p2 = a + n;
1235            vec2 p3 = b + n;
1236            vec2 p4 = b - n;
1237
1238            // Draw the line as 2 triangles, could be optimized
1239            // by using only 4 vertices and the correct indices
1240            // Also we should probably used non textured vertices
1241            // when line AA is disabled to save on bandwidth
1242            TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1243            TextureVertex::set(vertex++, p2.x, p2.y, 0.0f, 0.0f);
1244            TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1245            TextureVertex::set(vertex++, p1.x, p1.y, 0.0f, 0.0f);
1246            TextureVertex::set(vertex++, p3.x, p3.y, 0.0f, 0.0f);
1247            TextureVertex::set(vertex++, p4.x, p4.y, 0.0f, 0.0f);
1248
1249            // TODO: Mark the dirty regions when RENDER_LAYERS_AS_REGIONS is set
1250        }
1251
1252        // GL_LINE does not give the result we want to match Skia
1253        glDrawArrays(GL_TRIANGLES, 0, verticesCount);
1254    } else {
1255        // TODO: Handle the AA case
1256        for (int i = 0; i < count; i += 4) {
1257            TextureVertex::set(vertex++, points[i], points[i + 1], 0.0f, 0.0f);
1258            TextureVertex::set(vertex++, points[i + 2], points[i + 3], 0.0f, 0.0f);
1259        }
1260
1261        glLineWidth(1.0f);
1262        glDrawArrays(GL_LINES, 0, verticesCount);
1263    }
1264}
1265
1266void OpenGLRenderer::drawColor(int color, SkXfermode::Mode mode) {
1267    // No need to check against the clip, we fill the clip region
1268    if (mSnapshot->isIgnored()) return;
1269
1270    Rect& clip(*mSnapshot->clipRect);
1271    clip.snapToPixelBoundaries();
1272
1273    drawColorRect(clip.left, clip.top, clip.right, clip.bottom, color, mode, true);
1274}
1275
1276void OpenGLRenderer::drawRect(float left, float top, float right, float bottom, SkPaint* p) {
1277    if (quickReject(left, top, right, bottom)) {
1278        return;
1279    }
1280
1281    SkXfermode::Mode mode;
1282    if (!mCaches.extensions.hasFramebufferFetch()) {
1283        const bool isMode = SkXfermode::IsMode(p->getXfermode(), &mode);
1284        if (!isMode) {
1285            // Assume SRC_OVER
1286            mode = SkXfermode::kSrcOver_Mode;
1287        }
1288    } else {
1289        mode = getXfermode(p->getXfermode());
1290    }
1291
1292    // Skia draws using the color's alpha channel if < 255
1293    // Otherwise, it uses the paint's alpha
1294    int color = p->getColor();
1295    if (((color >> 24) & 0xff) == 255) {
1296        color |= p->getAlpha() << 24;
1297    }
1298
1299    drawColorRect(left, top, right, bottom, color, mode);
1300}
1301
1302void OpenGLRenderer::drawText(const char* text, int bytesCount, int count,
1303        float x, float y, SkPaint* paint) {
1304    if (text == NULL || count == 0 || (paint->getAlpha() == 0 && paint->getXfermode() == NULL)) {
1305        return;
1306    }
1307    if (mSnapshot->isIgnored()) return;
1308
1309    paint->setAntiAlias(true);
1310
1311    float length = -1.0f;
1312    switch (paint->getTextAlign()) {
1313        case SkPaint::kCenter_Align:
1314            length = paint->measureText(text, bytesCount);
1315            x -= length / 2.0f;
1316            break;
1317        case SkPaint::kRight_Align:
1318            length = paint->measureText(text, bytesCount);
1319            x -= length;
1320            break;
1321        default:
1322            break;
1323    }
1324
1325    // TODO: Handle paint->getTextScaleX()
1326    const float oldX = x;
1327    const float oldY = y;
1328    const bool pureTranslate = mSnapshot->transform->isPureTranslate();
1329    if (pureTranslate) {
1330        x = (int) floorf(x + mSnapshot->transform->getTranslateX() + 0.5f);
1331        y = (int) floorf(y + mSnapshot->transform->getTranslateY() + 0.5f);
1332    }
1333
1334    FontRenderer& fontRenderer = mCaches.fontRenderer.getFontRenderer(paint);
1335    fontRenderer.setFont(paint, SkTypeface::UniqueID(paint->getTypeface()),
1336            paint->getTextSize());
1337
1338    int alpha;
1339    SkXfermode::Mode mode;
1340    getAlphaAndMode(paint, &alpha, &mode);
1341
1342    if (mHasShadow) {
1343        mCaches.dropShadowCache.setFontRenderer(fontRenderer);
1344        const ShadowTexture* shadow = mCaches.dropShadowCache.get(paint, text, bytesCount,
1345                count, mShadowRadius);
1346        const AutoTexture autoCleanup(shadow);
1347
1348        const float sx = x - shadow->left + mShadowDx;
1349        const float sy = y - shadow->top + mShadowDy;
1350
1351        const int shadowAlpha = ((mShadowColor >> 24) & 0xFF);
1352
1353        glActiveTexture(gTextureUnits[0]);
1354        setupDraw();
1355        setupDrawWithTexture(true);
1356        setupDrawAlpha8Color(mShadowColor, shadowAlpha < 255 ? shadowAlpha : alpha);
1357        setupDrawBlending(true, mode);
1358        setupDrawProgram();
1359        setupDrawModelView(sx, sy, sx + shadow->width, sy + shadow->height, pureTranslate);
1360        setupDrawTexture(shadow->id);
1361        setupDrawPureColorUniforms();
1362        setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1363
1364        glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1365        finishDrawTexture();
1366    }
1367
1368    // Pick the appropriate texture filtering
1369    bool linearFilter = mSnapshot->transform->changesBounds();
1370    if (pureTranslate && !linearFilter) {
1371        linearFilter = fabs(y - (int) y) > 0.0f || fabs(x - (int) x) > 0.0f;
1372    }
1373
1374    glActiveTexture(gTextureUnits[0]);
1375    setupDraw();
1376    setupDrawDirtyRegionsDisabled();
1377    setupDrawWithTexture(true);
1378    setupDrawAlpha8Color(paint->getColor(), alpha);
1379    setupDrawColorFilter();
1380    setupDrawShader();
1381    setupDrawBlending(true, mode);
1382    setupDrawProgram();
1383    setupDrawModelView(x, y, x, y, pureTranslate, true);
1384    setupDrawTexture(fontRenderer.getTexture(linearFilter));
1385    setupDrawPureColorUniforms();
1386    setupDrawColorFilterUniforms();
1387    setupDrawShaderUniforms(pureTranslate);
1388
1389    const Rect* clip = pureTranslate ? mSnapshot->clipRect : &mSnapshot->getLocalClip();
1390    Rect bounds(FLT_MAX / 2.0f, FLT_MAX / 2.0f, FLT_MIN / 2.0f, FLT_MIN / 2.0f);
1391
1392#if RENDER_LAYERS_AS_REGIONS
1393    bool hasLayer = (mSnapshot->flags & Snapshot::kFlagFboTarget) && mSnapshot->region;
1394#else
1395    bool hasLayer = false;
1396#endif
1397
1398    mCaches.unbindMeshBuffer();
1399    if (fontRenderer.renderText(paint, clip, text, 0, bytesCount, count, x, y,
1400            hasLayer ? &bounds : NULL)) {
1401#if RENDER_LAYERS_AS_REGIONS
1402        if (hasLayer) {
1403            if (!pureTranslate) {
1404                mSnapshot->transform->mapRect(bounds);
1405            }
1406            bounds.intersect(*mSnapshot->clipRect);
1407            bounds.snapToPixelBoundaries();
1408
1409            android::Rect dirty(bounds.left, bounds.top, bounds.right, bounds.bottom);
1410            mSnapshot->region->orSelf(dirty);
1411        }
1412#endif
1413    }
1414
1415    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
1416    glDisableVertexAttribArray(mCaches.currentProgram->getAttrib("texCoords"));
1417
1418    drawTextDecorations(text, bytesCount, length, oldX, oldY, paint);
1419}
1420
1421void OpenGLRenderer::drawPath(SkPath* path, SkPaint* paint) {
1422    if (mSnapshot->isIgnored()) return;
1423
1424    GLuint textureUnit = 0;
1425    glActiveTexture(gTextureUnits[textureUnit]);
1426
1427    const PathTexture* texture = mCaches.pathCache.get(path, paint);
1428    if (!texture) return;
1429    const AutoTexture autoCleanup(texture);
1430
1431    const float x = texture->left - texture->offset;
1432    const float y = texture->top - texture->offset;
1433
1434    if (quickReject(x, y, x + texture->width, y + texture->height)) {
1435        return;
1436    }
1437
1438    int alpha;
1439    SkXfermode::Mode mode;
1440    getAlphaAndMode(paint, &alpha, &mode);
1441
1442    setupDraw();
1443    setupDrawWithTexture(true);
1444    setupDrawAlpha8Color(paint->getColor(), alpha);
1445    setupDrawColorFilter();
1446    setupDrawShader();
1447    setupDrawBlending(true, mode);
1448    setupDrawProgram();
1449    setupDrawModelView(x, y, x + texture->width, y + texture->height);
1450    setupDrawTexture(texture->id);
1451    setupDrawPureColorUniforms();
1452    setupDrawColorFilterUniforms();
1453    setupDrawShaderUniforms();
1454    setupDrawMesh(NULL, (GLvoid*) gMeshTextureOffset);
1455
1456    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1457
1458    finishDrawTexture();
1459}
1460
1461///////////////////////////////////////////////////////////////////////////////
1462// Shaders
1463///////////////////////////////////////////////////////////////////////////////
1464
1465void OpenGLRenderer::resetShader() {
1466    mShader = NULL;
1467}
1468
1469void OpenGLRenderer::setupShader(SkiaShader* shader) {
1470    mShader = shader;
1471    if (mShader) {
1472        mShader->set(&mCaches.textureCache, &mCaches.gradientCache);
1473    }
1474}
1475
1476///////////////////////////////////////////////////////////////////////////////
1477// Color filters
1478///////////////////////////////////////////////////////////////////////////////
1479
1480void OpenGLRenderer::resetColorFilter() {
1481    mColorFilter = NULL;
1482}
1483
1484void OpenGLRenderer::setupColorFilter(SkiaColorFilter* filter) {
1485    mColorFilter = filter;
1486}
1487
1488///////////////////////////////////////////////////////////////////////////////
1489// Drop shadow
1490///////////////////////////////////////////////////////////////////////////////
1491
1492void OpenGLRenderer::resetShadow() {
1493    mHasShadow = false;
1494}
1495
1496void OpenGLRenderer::setupShadow(float radius, float dx, float dy, int color) {
1497    mHasShadow = true;
1498    mShadowRadius = radius;
1499    mShadowDx = dx;
1500    mShadowDy = dy;
1501    mShadowColor = color;
1502}
1503
1504///////////////////////////////////////////////////////////////////////////////
1505// Drawing implementation
1506///////////////////////////////////////////////////////////////////////////////
1507
1508// Same values used by Skia
1509#define kStdStrikeThru_Offset   (-6.0f / 21.0f)
1510#define kStdUnderline_Offset    (1.0f / 9.0f)
1511#define kStdUnderline_Thickness (1.0f / 18.0f)
1512
1513void OpenGLRenderer::drawTextDecorations(const char* text, int bytesCount, float length,
1514        float x, float y, SkPaint* paint) {
1515    // Handle underline and strike-through
1516    uint32_t flags = paint->getFlags();
1517    if (flags & (SkPaint::kUnderlineText_Flag | SkPaint::kStrikeThruText_Flag)) {
1518        float underlineWidth = length;
1519        // If length is > 0.0f, we already measured the text for the text alignment
1520        if (length <= 0.0f) {
1521            underlineWidth = paint->measureText(text, bytesCount);
1522        }
1523
1524        float offsetX = 0;
1525        switch (paint->getTextAlign()) {
1526            case SkPaint::kCenter_Align:
1527                offsetX = underlineWidth * 0.5f;
1528                break;
1529            case SkPaint::kRight_Align:
1530                offsetX = underlineWidth;
1531                break;
1532            default:
1533                break;
1534        }
1535
1536        if (underlineWidth > 0.0f) {
1537            const float textSize = paint->getTextSize();
1538            const float strokeWidth = textSize * kStdUnderline_Thickness;
1539
1540            const float left = x - offsetX;
1541            float top = 0.0f;
1542
1543            const int pointsCount = 4 * (flags & SkPaint::kStrikeThruText_Flag ? 2 : 1);
1544            float points[pointsCount];
1545            int currentPoint = 0;
1546
1547            if (flags & SkPaint::kUnderlineText_Flag) {
1548                top = y + textSize * kStdUnderline_Offset;
1549                points[currentPoint++] = left;
1550                points[currentPoint++] = top;
1551                points[currentPoint++] = left + underlineWidth;
1552                points[currentPoint++] = top;
1553            }
1554
1555            if (flags & SkPaint::kStrikeThruText_Flag) {
1556                top = y + textSize * kStdStrikeThru_Offset;
1557                points[currentPoint++] = left;
1558                points[currentPoint++] = top;
1559                points[currentPoint++] = left + underlineWidth;
1560                points[currentPoint++] = top;
1561            }
1562
1563            SkPaint linesPaint(*paint);
1564            linesPaint.setStrokeWidth(strokeWidth);
1565
1566            drawLines(&points[0], pointsCount, &linesPaint);
1567        }
1568    }
1569}
1570
1571void OpenGLRenderer::drawColorRect(float left, float top, float right, float bottom,
1572        int color, SkXfermode::Mode mode, bool ignoreTransform) {
1573    // If a shader is set, preserve only the alpha
1574    if (mShader) {
1575        color |= 0x00ffffff;
1576    }
1577
1578    setupDraw();
1579    setupDrawColor(color);
1580    setupDrawShader();
1581    setupDrawColorFilter();
1582    setupDrawBlending(mode);
1583    setupDrawProgram();
1584    setupDrawModelView(left, top, right, bottom, ignoreTransform);
1585    setupDrawColorUniforms();
1586    setupDrawShaderUniforms(ignoreTransform);
1587    setupDrawColorFilterUniforms();
1588    setupDrawSimpleMesh();
1589
1590    glDrawArrays(GL_TRIANGLE_STRIP, 0, gMeshCount);
1591}
1592
1593void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1594        Texture* texture, SkPaint* paint) {
1595    int alpha;
1596    SkXfermode::Mode mode;
1597    getAlphaAndMode(paint, &alpha, &mode);
1598
1599    setTextureWrapModes(texture, GL_CLAMP_TO_EDGE, GL_CLAMP_TO_EDGE);
1600
1601    if (mSnapshot->transform->isPureTranslate()) {
1602        const float x = (int) floorf(left + mSnapshot->transform->getTranslateX() + 0.5f);
1603        const float y = (int) floorf(top + mSnapshot->transform->getTranslateY() + 0.5f);
1604
1605        drawTextureMesh(x, y, x + texture->width, y + texture->height, texture->id,
1606                alpha / 255.0f, mode, texture->blend, (GLvoid*) NULL,
1607                (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount, false, true);
1608    } else {
1609        drawTextureMesh(left, top, right, bottom, texture->id, alpha / 255.0f, mode,
1610                texture->blend, (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset,
1611                GL_TRIANGLE_STRIP, gMeshCount);
1612    }
1613}
1614
1615void OpenGLRenderer::drawTextureRect(float left, float top, float right, float bottom,
1616        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend) {
1617    drawTextureMesh(left, top, right, bottom, texture, alpha, mode, blend,
1618            (GLvoid*) NULL, (GLvoid*) gMeshTextureOffset, GL_TRIANGLE_STRIP, gMeshCount);
1619}
1620
1621void OpenGLRenderer::drawTextureMesh(float left, float top, float right, float bottom,
1622        GLuint texture, float alpha, SkXfermode::Mode mode, bool blend,
1623        GLvoid* vertices, GLvoid* texCoords, GLenum drawMode, GLsizei elementsCount,
1624        bool swapSrcDst, bool ignoreTransform, GLuint vbo, bool ignoreScale, bool dirty) {
1625
1626    setupDraw();
1627    setupDrawWithTexture();
1628    setupDrawColor(alpha, alpha, alpha, alpha);
1629    setupDrawColorFilter();
1630    setupDrawBlending(blend, mode, swapSrcDst);
1631    setupDrawProgram();
1632    if (!dirty) {
1633        setupDrawDirtyRegionsDisabled();
1634    }
1635    if (!ignoreScale) {
1636        setupDrawModelView(left, top, right, bottom, ignoreTransform);
1637    } else {
1638        setupDrawModelViewTranslate(left, top, right, bottom, ignoreTransform);
1639    }
1640    setupDrawPureColorUniforms();
1641    setupDrawColorFilterUniforms();
1642    setupDrawTexture(texture);
1643    setupDrawMesh(vertices, texCoords, vbo);
1644
1645    glDrawArrays(drawMode, 0, elementsCount);
1646
1647    finishDrawTexture();
1648}
1649
1650void OpenGLRenderer::chooseBlending(bool blend, SkXfermode::Mode mode,
1651        ProgramDescription& description, bool swapSrcDst) {
1652    blend = blend || mode != SkXfermode::kSrcOver_Mode;
1653    if (blend) {
1654        if (mode < SkXfermode::kPlus_Mode) {
1655            if (!mCaches.blend) {
1656                glEnable(GL_BLEND);
1657            }
1658
1659            GLenum sourceMode = swapSrcDst ? gBlendsSwap[mode].src : gBlends[mode].src;
1660            GLenum destMode = swapSrcDst ? gBlendsSwap[mode].dst : gBlends[mode].dst;
1661
1662            if (sourceMode != mCaches.lastSrcMode || destMode != mCaches.lastDstMode) {
1663                glBlendFunc(sourceMode, destMode);
1664                mCaches.lastSrcMode = sourceMode;
1665                mCaches.lastDstMode = destMode;
1666            }
1667        } else {
1668            // These blend modes are not supported by OpenGL directly and have
1669            // to be implemented using shaders. Since the shader will perform
1670            // the blending, turn blending off here
1671            if (mCaches.extensions.hasFramebufferFetch()) {
1672                description.framebufferMode = mode;
1673                description.swapSrcDst = swapSrcDst;
1674            }
1675
1676            if (mCaches.blend) {
1677                glDisable(GL_BLEND);
1678            }
1679            blend = false;
1680        }
1681    } else if (mCaches.blend) {
1682        glDisable(GL_BLEND);
1683    }
1684    mCaches.blend = blend;
1685}
1686
1687bool OpenGLRenderer::useProgram(Program* program) {
1688    if (!program->isInUse()) {
1689        if (mCaches.currentProgram != NULL) mCaches.currentProgram->remove();
1690        program->use();
1691        mCaches.currentProgram = program;
1692        return false;
1693    }
1694    return true;
1695}
1696
1697void OpenGLRenderer::resetDrawTextureTexCoords(float u1, float v1, float u2, float v2) {
1698    TextureVertex* v = &mMeshVertices[0];
1699    TextureVertex::setUV(v++, u1, v1);
1700    TextureVertex::setUV(v++, u2, v1);
1701    TextureVertex::setUV(v++, u1, v2);
1702    TextureVertex::setUV(v++, u2, v2);
1703}
1704
1705void OpenGLRenderer::getAlphaAndMode(SkPaint* paint, int* alpha, SkXfermode::Mode* mode) {
1706    if (paint) {
1707        if (!mCaches.extensions.hasFramebufferFetch()) {
1708            const bool isMode = SkXfermode::IsMode(paint->getXfermode(), mode);
1709            if (!isMode) {
1710                // Assume SRC_OVER
1711                *mode = SkXfermode::kSrcOver_Mode;
1712            }
1713        } else {
1714            *mode = getXfermode(paint->getXfermode());
1715        }
1716
1717        // Skia draws using the color's alpha channel if < 255
1718        // Otherwise, it uses the paint's alpha
1719        int color = paint->getColor();
1720        *alpha = (color >> 24) & 0xFF;
1721        if (*alpha == 255) {
1722            *alpha = paint->getAlpha();
1723        }
1724    } else {
1725        *mode = SkXfermode::kSrcOver_Mode;
1726        *alpha = 255;
1727    }
1728}
1729
1730SkXfermode::Mode OpenGLRenderer::getXfermode(SkXfermode* mode) {
1731    if (mode == NULL) {
1732        return SkXfermode::kSrcOver_Mode;
1733    }
1734    return mode->fMode;
1735}
1736
1737void OpenGLRenderer::setTextureWrapModes(Texture* texture, GLenum wrapS, GLenum wrapT) {
1738    bool bound = false;
1739    if (wrapS != texture->wrapS) {
1740        glBindTexture(GL_TEXTURE_2D, texture->id);
1741        bound = true;
1742        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, wrapS);
1743        texture->wrapS = wrapS;
1744    }
1745    if (wrapT != texture->wrapT) {
1746        if (!bound) {
1747            glBindTexture(GL_TEXTURE_2D, texture->id);
1748        }
1749        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, wrapT);
1750        texture->wrapT = wrapT;
1751    }
1752}
1753
1754}; // namespace uirenderer
1755}; // namespace android
1756